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1.
The immunodominant 33/35kDa antigen of a Theileria isolate from West Java, Indonesia, was characterised and immuno-affinity purified by use of a monoclonal antibody, KUL-a4, and was shown to be representative of the T. orientalis/sergenti/buffeli group. The aminoterminal sequence of the purified 35kDa peptide (20 residues) was determined by automated Edman degradation and found to correspond to the predicted amino acid sequence of a prospective p33 gene previously sequenced from the same isolate. The cleavage site of a putative signal peptide was identified and conforms the (-3, -1) rule for signal peptidases. The existence of dimeric and trimeric forms of the p33/35 antigen is hypothesised from Western blot profiles. KUL-a4 appeared specific for the T. orientalis/sergenti/buffeli group. It did not recognise in indirect fluorescence antibody test (IFAT), intraerythrocytic bodies of Anaplasma marginale or piroplasms and schizonts of T. mutans, T. parva and T. annulata, whereas cattle antisera raised to these species showed cross-reactivity in IFAT. It however, appeared weakly cross-reactive in Western blot and ELISA, with the 34kDa piroplasm antigen of one T. annulata (Gharb) isolate. The present study indicates that the isolated antigen belongs to the p33/34 antigen family described within the T. sergenti/orientalis/buffeli group, and documents the group-specificity of one of its epitopes.  相似文献   
2.
In a cross-sectional study, performed between October 2002 and April 2003 on 55 Danish dairy herds with 6161 predominantly Holstein Friesian cows the prevalence of 9 hoof lesions was determined.

All test-day yields (TDY) of kg energy corrected milk (ECM) in the lactation of diagnosis were recorded. For the purpose of including hoof lesions in a decision support model an attempt was made to aggregate the lesions into digital dermatitis (DD), other interdigital diseases (OID, infectious diseases other than DD) and hoof horn diseases (HHD, related to metabolic disorders and trauma). A division was made based on the stage of lactation in which the lesions were diagnosed; during the first 100 days in milk, between days 101 and 200 and between days 201 and 305. Associations between the presence of hoof lesions at trimming and milk production were analyzed by linear mixed modeling at the cow level, clustered within herd. The data of primiparous cows was analyzed separately from the multiparous cows.

Based on the associations between TDY and the individual lesions aggregated into HHD, this aggregation as initially planned could not be justified and was therefore not maintained. For OID the value of early diagnosis was apparent; an early diagnosis and early treatment (<101 DIM) was associated with either a positive value or a value less negative compared to a diagnosis and treatment in late lactation (201–305 DIM). This pattern was not as clearly present for the other lesions.  相似文献   

3.
High-pressure liquid chromatography with an ion-exchange column combined with graphite furnace atomic absorption spectrometry was used to analyse commercial formulations of sodium hydrogen methylarsonate (MSMA). No arsenite or arsenate salts or dimethylarsinic acid were detected as contaminants in the formulations, and the MSMA concentrations were found to be in accordance with the concentrations given on the containers.  相似文献   
4.
The combined occurrence of ocular pigment deposition and glaucoma has been described in Cairn Terriers. Recently, this condition was also observed in two other breeds: the Boxer (two cases) and the Labrador Retriever (one case). Six dogs were referred to the Ophthalmology section of the Department of Clinical Sciences of Companion Animals and to a private referral clinic because of glaucoma or blindness in one or both eyes. In five cases ophthalmic examination showed pigment depositions in the sclera around the entire circumference of the perilimbal zone. Eight enucleated eyes (four eyes of two Cairn Terriers, three eyes of two Boxers and one eye of a Labrador Retriever) were examined microscopically. All eyes showed the same findings: an extensive infiltration of large melanin-containing cells with an eccentric nucleus, located in the iris, ciliary body, retina, choroids and sclera. Transmission electron microscopy of two of the examined eyes revealed that the morphology of most of these cells was consistent with melanophages. While reports in the veterinary literature concerning this condition are limited the cells concerned have been described to be melanocytes. Further research is needed to conclusively identify the cell type. As described in the present report, the histologic and transmission electron microscopic findings suggest a different etiology of the ocular pigment deposition and glaucoma compared with the pigment dispersal syndrome in humans.  相似文献   
5.
6.
Ma G  Li Y  Jin Y  Du S  Kok FJ  Yang X 《Public health nutrition》2007,10(8):848-854
OBJECTIVES: To assess the intake inadequacy and food sources of zinc of people in China. DESIGN AND SUBJECTS: Diets of 68 962 subjects aged 2-101 years (urban 21 103, rural 47,859) in the 2002 China National Nutrition and Health Survey were analysed. Dietary intake was assessed using 24-hour recall for three consecutive days. Zinc intake inadequacy was calculated based on values suggested by the World Health Organization. RESULTS: The median zinc intake ranged from 4.9 mg day- 1 (urban girls, 2-3 years) to 11.9 mg day-1 (rural males, 19+ years). The zinc density of urban residents (2-3 to 19+ years) was 5.0-5.3 mg day-1 (1000 kcal)-1, significantly higher than that of their rural counterparts (4.7-4.8 mg day-1 (1000 kcal)-1). Differences in food sources of zinc from cereal grains (27.4-45.1 vs. 51.6-63.2%) and animal foods (28.4-54.8 vs. 16.8-30.6%) were found between urban and rural residents. Zinc from vegetables and fruits (8.2-13.8 vs. 9.7-12.4%) and legumes (1.3-3.3 vs. 2.5-3.4%) was comparable between urban and rural residents. The proportion of zinc intake inadequacy ranged between 2.8% (urban females, 19+ years) and 29.4% (rural lactating women). Rural residents had higher proportions of zinc intake inadequacy than their urban counterparts. Significantly higher proportions of zinc inadequacy were found in the category of phytate/zinc molar ratio >15 for both rural and urban residents. CONCLUSIONS: About 20% of rural children are at risk of inadequate zinc intake, with phytate as a potential important inhibitor. Moreover, lactating women are also considered a vulnerable group.  相似文献   
7.
With the increase in abandoned agricultural lands in Western Europe, knowledge on the successional pathways of newly developing forests becomes urgent. We evaluated the effect of time, soil type and dominant species type (shade tolerant or intolerant) on the development during succession of three stand attributes: above-ground biomass, stand height (HT) and stem density (SD). Additionally, we compared above-ground biomass (AGB) in natural and planted forests, using ten chronosequences (8 from the literature and 2 from this study). Both AGB and HT increased over time, whereas SD decreased. HT, SD and AGB differed among species types. For example, birch had greater HT than alder, willow and ash at a similar age and had higher SD than pine and oak at a similar age. However, birch showed lower AGB than pine. HT and AGB differed among soil types. They were higher in rich soil than in poor soils. Comparative analysis between chronosequences showed an effect of the regeneration method (natural regeneration vs plantation) on above-ground biomass. Planted sites had higher AGB than natural regeneration. Time, soil type, species and regeneration method influenced the mechanism of stand responses during secondary succession. These characteristics could be used to clarify the heterogeneity and potential productivity of such spontaneously growing temperate forest ecosystems.  相似文献   
8.
In the freshwater area of Vietnam's Mekong Delta, Barbodes gonionotus (Bleeker), Cyprinus carpio L. and Oreochromis niloticus (L.) are often reared together in rice fields. The survival rate and specific growth rate (SGR) of C. carpio showed a large variance. To understand the underlying reasons for this variation, we used multiple regressions for the variables SGR and survival rate, using the results of eight experiments in such polycultures at the Co Do rice–fish experimental station. The SGR of C. carpio declined with increasing rice density. Interspecific competition with O. niloticus also had a negative effect on C. carpio SGR. When fertilizer or manure is added to the trench of the rice–fish field or when extra food can be given to the fish, O. niloticus seems more appropriate than C. carpio. The survival rate of C. carpio depended on season, C. carpio stocking weight and density and the biomass of wild fish species. To obtain higher survival rates, one should stock fewer fish but of a larger size, after thorough eradication of wild fish species.  相似文献   
9.
Trichogaster pectoralis Regan is often cultured successfully in rice fields in South‐east Asia. However, since the advent of high‐yielding rice varieties and intensive rice cropping, several reports suggest poorer growth performance of the species. In this paper, we investigated the growth performance of T. pectoralis in rice–fish systems characterized by intensive rice culture and extensive to semi‐intensive polyculture of Oreochromis niloticus (L.), Cyprinus carpio L. and Barbodes gonionotus (Bleeker). In these systems, T. pectoralis recorded negative net productions. This was mainly the result of a negative specific growth rate (SGR) when fish had to stay in the trench (?0.519% body weight day?1) or when fish had free access to the rice crop (?0.081). Only when harvested rice plants were allowed to generate new tillers (ratooning) did T. pectoralis perform slightly better (0.453% body weight day?1). The SGR of T. pectoralis was low owing to a lack of food in intensive rice systems. The other species, all with SGR values higher than 1% body weight day?1, clearly had a competitive advantage over T. pectoralis. We concluded that intensification of rice cropping did indeed result in poor T. pectoralis growth. Successful T. pectoralis culture is only possible in areas of traditional rice cropping.  相似文献   
10.
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